CD133/CD49a discriminate between human pluripotent stem cell-derived pancreatic beta and alpha cells.

Human pluripotent stem cell (hPSC)-derived pancreatic beta cells provide an unlimited cell source for disease modeling and drug development. Generating highly purified beta cell populations from hPSCs remains challenging due to contamination by off-target and polyhormonal cells. Here, we present a robust cell-sorting-based purification strategy to enhance stem cell-derived beta (SC-beta) cell purity. Building on our previous work, we identified CD133 (PROM1) as a beta cell-enriched surface marker capable of distinguishing SC-beta cells from SC-alpha cells. Combining CD133 with the pan-endocrine marker CD49a (ITGA1) significantly increased beta cell enrichment while drastically reducing the fractions of alpha cells, polyhormonal cells, and ductal cells. This effect was consistent across multiple hPSC lines and differentiation protocols. Our approach yields SC-beta cell preparations with markedly improved purity, thereby advancing their application in disease modeling and drug development.